Company to unveil wireless chargers for cell phones and netbooks

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SAN FRANCISCO — Powermat USA helped consumers cut some power cords last year by selling mats that juiced up gadgets placed on top of them. They weren't seamless solutions, though, because they required add-ons such as special cell phone cases.

Now, the company is trying to streamline wireless charging with a battery that replaces the one that comes in your cell phone. Called the Powerpack, it lets users charge phones by just plopping them down on one of the company's mats.

Powermat was announcing the Powerpack on Tuesday at the International Consumer Electronics Show in Las Vegas, along with other wireless charging products it will release this year.

The batteries are expected to cost $40 and begin selling in May. At CES this week, Powermat will show about a dozen Powerpacks that will be compatible with more than 50 cell phones from such companies as Nokia Corp., HTC Corp. and BlackBerry maker Research In Motion Ltd.

Powermat uses induction to charge electronics. When you place a Powermat-enabled device on one of its mats, the two exchange a "handshake" using RFID, or radio-frequency identification technology. The mat identifies the device, determines how much power it needs and transfers energy to it. Once a device is fully charged, Powermat stops the electricity from flowing.

The technology can't pass a charge through metal, though, so for phones with metal battery doors, the company will sell its own phone backs that let the Powerpack work, said the company's vice president of marketing, Beth Harrison Meyer.

Eventually, she said, Powermat expects phone makers to build its technology into the device.

Other products Powermat expects to unveil at CES include a foldable wireless charging mat with its own battery, so you could charge gadgets without plugging the mat in. A version of the mat that can charge one device will cost $69, and a version that can charge two will cost $99. It is due for release in the third quarter.

Powermat will also show a mat that can charge small "netbook" computers from such companies as AsusTek Computer Inc., Dell Inc. and Lenovo Group Ltd. Powermat expects to start selling this product in the third quarter for $149.